Question

Помогите плиз срочно

1:||х|-7|=9

Даю 20 балов

Answer 1

$\dfrac{1}{\Big||x|-7\Big|} =9\\\\\\\Big||x|-7\Big|=\dfrac{1}{9}\\\\\\\left[\begin{array}{ccc}|x|-7=\dfrac{1}{9} \\|x|-7=-\fdrac{1}{9} \end{array}\right \\\\\\\left[\begin{array}{ccc}|x|=7\dfrac{1}{9} \\|x|=6\dfrac{8}{9} \end{array}\right\\\\1) \ |x|=7\dfrac{1}{9} \\\\x_{1}=7\dfrac{1}{9} \ ; \ x_{2}=-7\dfrac{1}{9} \\\\2) \ |x|=6\dfrac{8}{9} \\\\x_{3}=6\dfrac{8}{9} \ ; \ x_{4}=-6\dfrac{8}{9}$